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A biting wind and falling temperatures—let alone a rocky economy—didn’t put a damper on festivities at the annual meeting of the Society of Cosmetic Chemists (SCC), which was held Dec. 10-11 in New York City. Long-time industry veteran Janusz Jachowitz received the Maison G. deNavarre Medal award during the awards luncheon (see sidebar), while Robert Lochhead took the gavel from Gary Agisim as president of the Society. The meeting also included more than 80 poster presentations from industry suppliers.

The annual event got underway Dec. 10 with a session on sunscreens moderated by Mindy S. Goldstein. Craig Bonda, Hallstar, detailed how his DEXSTER (DEactivation of EXcitedSTates by Emissions and Radiationless pathways) system enables formulators to understand all the things that happen between excited states and ground states of a UV filter.

Bonda noted that butyl methoxydibenzoyl- methane’s (BMDM) short-lived singlet excited state can be quenched by adding a methoxy to the basic cyanodiphenyl acrylate framework. He said that at equal weight concentrations, ethylhexyl meth-oxycrylene is more effective than octocrylene at preserving avobenzone’s UVA and UVB absorbance in the absence of octyl methoxycinnamate (OMC). Bonda also concluded that ethylhexyl methoxycrylene is far superior to octocrylene at preserving BMDM’s UVA and UVB absorbance in the presence of OMC. Finally, formulations containing BMDM and OMC can achieve high UVA protection factors when photostabilized with ethylhexyl methoxycrylene.

Irritation is a problem with some UV formulas, but Howard Epstein of EMD Chemicals explained how encapsulate

In presenting the award, Bob Bianchini of Johnson & Johnson, told the audience that Jachowicz has more than 100 patents and publications, has been a recipient of the Thomas A. Edison award and is considered the “best in the business” when it comes to hair care.

In accepting the award, Jachowicz thanked the Society, his employers during his 21-year career and his colleagues. “Formulators are the essence of the industry,” he said.

technology and a focused formulation strategy can reduce dermal UV filter uptake in the skin and boost in vivo SPF/UVA. A sol-gel encapsulation process was used to trap BMDM and OMC. The process not only provided an enhanced margin of safety due to reduced dermal penetration of sunscreen, it also gives formulators the ability to formulate OMC with avobenzone to create a broad range of effective sunscreen products. In tests, approximately 92.87% of the applied dose of the free sunscreen and 96.74% of encapsulated sunscreen remained on the skin surface. With respect to total skin absorption, 70% less sunscreen was measured in receptor fluid, epidermis and dermis.

The encapsulation technique has other advantages; for example, you can put the active in a water phase and encapsulates can be used to boost SPF. However, Epstein warned that the encapsulation technology is very formulation dependent—alcohol will erode it.

Moving from chemical sunscreens to physical ones, Pascal Delrieu of Kobo Products explained the benefits of non-nano zinc oxide. With non-government organizations warning about the potential dangers of ultra-small molecules, nano has become a no-no for some cosmetic chemists. Nano-sized molecules range from 1-100nm. Kobo researchers found a nano-alternative for sunscreen that was recently developed by Sumitomo Osaka Cement. The primary particles of ZnO-C are in the 100-400nm range. Electron microscopy studies show that no particles are smaller than 100nm. In-vivo results showed that ZnO-C has lower attenuation than ultrafine ZnO. But despite its larger size, ZnO-C still delivered a critical wavelength over 380nm. Another grade, treated with jojoba esters, demonstrated attenuation power equal to its nano counterparts. The jojoba ester treatment causes the primary particles to form aggregates and meet the non-nano criteria.

Moving on to something completely different, Nadrian C. Seeman of New York University delved into the complex world of DNA modeling in the SCC Frontiers of Science lecture. In his opening remarks, he urged the audience to put aside DNA’s traditional double-helix image and introduced everyone to a variety of branched species and Borromean rings. Multi-tile DNA arrays have also been used to organize gold nanoparticles in specific arrangements, according to Seeman.

Modeling and Data Assessment

Thursday’s afternoon session, devoted to modeling and data assessment, was moderated by Martha Tate of Kimberly-Clark. George Fitzgerald of Accelrys, Inc., detailed an advanced regression model for soap reformulation. His method leverages ingredient information, together with rules to create reliable regression approaches that answer the question, “what was it about that particular ingredient which worked?”

His software methodology puts the focus of the modeling not so much on the use of a statistical method once the data is gathered, but on the gathering of the data in the first place.

“Our approach produces predictive models which can be used not simply to understand existing processes, but to discover new ones,” he concluded. “This distinguishes it from approaches which treat data using categorical modeling methods.”

James Hayward, Applied DNA Sciences, put a different spin on DNA and its applications when he explained how the material can be used to authenticate individual ingredients, batches and even entire product lines. Hayward noted that the global cosmetics and toiletries industry loses $3 billion a year to counterfeiters. DNA markers, he said, can be used to defend the supply chain and even check compliance in clinical tests.

Evaluating Skin Radiance

David Boudier explained Silab’s approach to evaluating skin radiance. The study was conducted on 100 volunteers using a VISIA CR device to capture images for the instrumental assessment and via sensory evaluation.

Expert judge evaluation helps to get information on the visual perception of the skin complexion and gives a description of the skin state on different parameters, while the image analysis method gives information on parameters associated to the way light is returned to the skin.

The session’s final speaker, Dominik Imfeld, DSM Nutritional Products, explained how his company used snake venom as a biomimetic design model for the treatment of skin wrinkles. Specifically, DSM isolated Waglerin-1 in snake venom, which is a polypeptide with a chain length of 22 amino acids, a molecular mass of 2522Da and an intramolecular disulphide bond between Cys9 and Cys13. Researchers created an H-beta-Ala-Pro-Dab-NHbenzyl peptide derivative, prepared it in a cosmetic formulation at 100ppm and compared it to commercially-available acetyl hexapeptide-3 (50ppm). The DSM material proved to have significant advantages over existing wrinkle reducers on the market, according to the test results.

Friday’s technical program included a morning session on skin biology moderated by Randy Wickett, University of Cincinnati.

Formulation Fundamentals

The afternoon session, moderated by Lochhead of the University of Southern Mississippi, was devoted to formulation fundamentals. The keynote award lecture by Dr. Ricardo Diez of Chanel, Inc. was sponsored by Ruger Chemical.

Diez provided a review of the progress of foaming cleansing products during the past 50 years. His presentation focused on key improvements in the foaming cleanser category since the International Federation of Societies of Cosmetic Chemists (IFSCC) was founded in 1959. The timeline of the presentation started in the 1920s, when soap (first generation) was the only available cleanser. The second generation of cleansers resulted from the discovery of new surfactants in Germany in the late 1920s. According to Diez, modern surfactant-based cleansers offer, relative to soap, improved mildness, lathering, cleansing and rinsing, as well as convenience. These advanced hydrating cleansers are based on surfactants. Cleansers with reduced irritation to the eye and skin, first patented in the 1950s, were the basis of the third generation, represented by mildness. The fourth generation was described as products with conditioning benefits to hair or skin achieved by the deposition of conditioning agents. The fifth generation was presented as the most advanced, for it offers real hydration to the skin, in addition to cleansing, mildness and conditioning.

Diez also discussed the many benefits that specialty facial cleansers can impart. For example, they provide niche benefits such as antibacterial and acne control, which in some countries, are considered drug claims. These days, some facial cleansers command high prices and this trend has opened the door to new formulations and other raw materials, which may lead to innovative products in the future.

Lisa Flugge-Berendes of Kimberly-Clark Corporation presented data on how to improve moisturization properties of hand sanitizer formulations. It is well known that alcohol-based sanitizers can be drying and irritating to the skin with repeated usage. Her team investigated two delivery systems—alcohol-gel and non-aerosol pump-foaming alcohol solution. They contained humectant and occlusive ingredients to counteract the drying effects of alcohol and offer superior moisturization compared to other similarly marketed products. Moisturization levels were determined using industry standard of conductance. Measurements were taken before application and at 30 and 120 minutes post application on the forearm to determine moisturization levels. Alcohol level provides antibacterial efficacy against commonly found skin surface bacteria such as staphylococcus, streptococcus, pseudomonas and trichophyton which are capable of causing primary, secondary, systemicand even nerve infection to compromised skin. It was pointed out that on average, the face is touched around 15 times an hour. Hospital-acquired infections caused 100,000 deaths in 2002 and cost $28-33 billion annually. Hence hand hygiene compliance is a solution depending upon effectiveness of prevention measures.

Rebecca Peevers of Croda UK presented data on the impact of white base ingredients choice in meeting the performance brief for lipstick formulations. At the present time, there is little information known about how different waxes such as candelilla, carnuba and ceresin, which are common in lipstick formulations, solidify different oils. Her presentation focused specifically on the firmness of the base and correlated this to the hardness and pay-off of the fully formulated stick. Hardness values were assessed using the texture analyzer and the pay-off assessment was conducted utilizing mechanical arm apparatus. In all 19 oils were assessed: castor oil, PPG-15 stearyl ether, propylene glycol isostearate, isostearyl isostearate, isostearyl alcohol, triisostearin, trimethylolpropane triisostearate, polyglyceryl-3 diisostearate, ethylhexyl cocoate, ethylhexyl pelargonate, pentaerythrityl tetracaprylate/caprate, PPG-3 benzyl ether myristate, isotridecyl isononanoate, di-PPG-2 myreth-10 adipate, PCA dimethicone, pentaerythrityl isostear- ate/caprate/caprylate/adipate, PPG-3 hydrogenated castor oil, di-PPG-3 myristyl ether adipate and pentaerythrityltetra- isostearate.

All the oils were assessed for oil/wax interaction. Several of the oils, formed very good oil/wax structures and hence they could be used to increase the hardness of soft lipstick formulations. More specifically, castor oil proved to be a high firming oil (9000g) along with di-PPG-2 myreth-10 adipate (8600g), polyglyceryl-3 diisoso- stearate (7600g) and PPG-3 hydrogenated castor oil (6400g). Isostearyl alcohol proved to be a low structuring oil at 2500g.

Her study clearly established that the firmness of the lipsticks inversely correlate to the level of pay-off allowing both firmness and pay-off to be controlled by altering the formulation as required.